Moorea's skyline arrives before the island does: eight saw-toothed green ridges lifting out of the Pacific, half an hour by ferry from Tahiti, in French Polynesia. They usually trail a collar of cloud, and one of them, Mou'aputa, has a hole punched clean through its summit. In the Tahitian story the hero Pai threw his spear from Tautira, fifty-five kilometres away, and drove it through the mountain to wake the islanders before thieves could carry off the ridge next door. That ridge is Mount Rotui, the blade of rock between Cook's Bay and Opunohu Bay, the two deep inlets cut into the north coast of a roughly heart-shaped island. A road winds up the green interior to the Belvedere lookout, where the two bays sit either side of Rotui. Cook never anchored in the one that carries his name; his ships lay in Opunohu, and the name settled on the wrong water and stayed. Trails climb from the valley floor into humid forest under Mou'aputa, and the higher clearings open onto the reef and lagoon.
Almost everything else here happens in the water. From July to November humpback whales come in from the open ocean to nurse their calves just beyond the barrier reef. Swimming with whales is banned outright in most countries. Here a licence allows it, and a boat carries a few swimmers at a time to slip into the blue while a mother and calf drift past below. The reef is one of the most closely watched on Earth, followed since 2004 through five bleaching events, and each time the coral has grown back, reseeded by larvae from reefs hundreds of kilometres away. The best of it needs no boat at all. On the north shore you wade out waist-deep over sand, and blacktip reef sharks slip past your legs while broad stingrays glide over your feet. There is no cage and no barrier, only water clear to the bottom, the reef floor underfoot, and the same eight ridges standing over you that came up out of the sea on the way in.